This best-selling book is now expanded and updated, providing a clear, concise, and comprehensive view of how to select, install, and maintain electrodes, control valves, and control strategies for pH applications critical for product and water quality in the process industry. The book covers every aspect of system design including the mixing and reagent piping requirements that are important for a successful application. The essential concepts are summarized as key insights and the best practices are presented as rules of thumb throughout the book. The emerging capability of dynamic online pH estimators is explored to make existing pH measurements faster and more reliable. The latest developments in advanced batch control, adaptive control, linear reagent demand control, and model predictive control are presented to reduce reagent consumption and variability. A Microsoft Excel workbook file is included that lets users generate titration curves and analyze pH control system performance. A virtual plant is also offered to prototype and study pH control systems. The dynamic process models and control system modules for the virtual plant require the use of DeltaV SimulatePro and HYSYS Plant licenses.